Upgrading from 5.211 to Current version 10.13

How do I keep all the settings when upgrading to a new install? Will the backup tool work between the versions?

Thank you,

nope. as painful as it will be you really have only two choices. fresh boot of the new system and ,manually apply the config or run all the updates to get you from where you are to where you want to go.

Option 3 is to migrate settings to a fresh install:
http://wiki.freepbx.org/display/PPS/Elastix+and+PBXinaFlash+to+FreePBX+Distro+Conversion+Tool